Search results

1

Magnetic Properties of La_{0.8}K_{0.2}MnO_{3} Nanoparticles

100%

Mihalik M., Zentková M., Briančin J., Fitta M., Mihalik M., Lazúrová J., Vavra M.

Acta Physica Polonica A

|

2014

|

vol. 126

|

issue 1

312-313

EN

Magnetic properties of La_{0.8}K_{0.2}MnO_{3} have been studied on nanoparticles prepared by glycine-nitrate method. Crystal structure and particles size were modified by heat treatment. Crystal structure changes from orthorhombic (space group Pbma) to rhombohedral (space group R-3c) after annealing at 600°C/2 hours. The average size of particle varies with annealing from about 30 nm to 135 nm. The Curie temperature T_{C} and the saturated magnetization μ_{s} increase with annealing. The exchange bias effect was observed on samples with particles size smaller than 60 nm.

2

Magnetic Properties of NdFe_{0.9}Mn_{0.1}O_{3}

84%

Zentková M., Lazúrová J., Kováč J., Mihalik M., Mihalik M., Briančin J., Fitta M., Kusigerski V.

Acta Physica Polonica A

|

2014

|

vol. 126

|

issue 1

306-307

EN

In our paper we study effect of Mn for Fe substitution on magnetic properties of NdFe_{x-1}Mn_{x}O_{3} compounds for x=0 and 0.1, which have been grown by the OFZ technique. The Néel temperature decreases from T_{N1}=691 K to T_{N1}=621 K, and the anomaly in AC susceptibility, related to spin reorientation, vanishes with Mn substitution. Low temperature heat capacity measurement for sample with x=0.1 revealed that substitution of Mn for Fe shifts a Schottky-type anomaly at T_{sh} to higher temperatures. Another anomaly is generated by doping at T_{max}=11 K. The anomaly is smeared out by magnetic field, confirming its magnetic origin.

3

Magnetic Properties of La_{0.85}Ag_{0.15}MnO_{3} Nano-Powders Under Pressure

84%

Antoňák M., Mihalik M., Zentková M., Mihalik M., Vavra M., Lazúrová J., Fitta M., Balanda M.

Acta Physica Polonica A

|

2014

|

vol. 126

|

issue 1

296-297

EN

In our paper we present effect of pressure on magnetic properties of La_{0.85}Ag_{0.15}MnO_{3} nanopowders prepared by glycine-nitrate method. The particle size and crystal structure were modified by heat treatment. The average size of particle varies from about 25 nm for as prepared sample to 60 nm for annealed sample. Crystal structure changes from orthorhombic to rhombohedral after annealing at 600 °C/2 hours. The Curie temperature increases with annealing and is more than doubled after annealing at 600 °C/2 hours. The exchange bias phenomenon was observed in samples with orthorhombic crystal structure with average particle size of about 25 nm. Pressure effect on the Curie temperature T_{C}, saturated magnetization μ_{s} and exchange bias field H_{E} is negligible in this case. In the case of the samples with rhombohedral structure, T_{C}, μ_{s} and remnant magnetization μ_{r} increase with pressure; the coercive field decreases with pressure.

4

Effect of the Jahn-Teller Distortion on Double Exchange Interaction in La_{0.8}K_{0.2}MnO₃ Nanoparticles

84%

Mihalik M., Zentková M., Vavra M., Mihalik Jr. M., Lazúrová J., Girman V., Konieczny P., Fitta M., Il'kovič S.

Acta Physica Polonica A

|

2017

|

vol. 131

|

issue 4

875-877

EN

Electric resistance and effect of hydrostatic pressure on magnetic properties has been studied on the La_{0.8}K_{0.2}MnO₃ nanoparticles. Magnetic phase transition is affected by pressure only slightly, the Curie temperature T_{C} decreases with the rate of -1.02 K/GPa, on samples with orthorhombic structure where the Jahn-Teller distortion of lattice is large. On the other hand, T_{C} increases with the rate of 20.1 K/GPa on samples with rhombohedral structure, where the Jahn-Teller distortion of lattice is absent. Insulator type of electrical resistance is characteristic feature of sample with large Jahn-Teller distortion of lattice and insulator-metal transition was observed on samples where the Jahn-Teller distortion is negligible. Our results are in line with theoretical calculation predicting that double exchange interaction is suppressed by the Jahn-Teller distortion.

5

Magnetic Systems at Criticality: Different Signatures of Scaling

68%

Pełka R., Konieczny P., Fitta M., Czapla M., Zieliński P., Bałanda M., Wasiutyński T., Miyazaki Y., Inaba A., Pinkowicz D., Sieklucka B.

Acta Physica Polonica A

|

2013

|

vol. 124

|

issue 6

977-989

EN

Different aspects of critical behaviour of magnetic materials are presented and discussed. The scaling ideas are shown to arise in the context of purely magnetic properties as well as in that of thermal properties as demonstrated by magnetocaloric effect or combined scaling of excess entropy and order parameter. Two non-standard approaches to scaling phenomena are described. The presented concepts are exemplified by experimental data gathered on four representatives of molecular magnets.

Refine search results

5 Acta Physica Polonica A

1 2017

3 2014

1 2013

5 Fitta M.

4 Lazúrová J.

4 Mihalik M.

4 Zentková M.

3 Vavra M.

2 Briančin J.

2 Konieczny P.

1 Antoňák M.

1 Balanda M.

1 Bałanda M.

1 Czapla M.

1 Girman V.

1 Il'kovič S.

1 Inaba A.

1 Kováč J.

1 Kusigerski V.

1 Mihalik Jr. M.

1 Miyazaki Y.

1 Pełka R.

1 Pinkowicz D.

1 Sieklucka B.

1 Wasiutyński T.

1 Zieliński P.

Magnetic Properties of La_{0.8}K_{0.2}MnO_{3} Nanoparticles

Magnetic Properties of NdFe_{0.9}Mn_{0.1}O_{3}

Magnetic Properties of La_{0.85}Ag_{0.15}MnO_{3} Nano-Powders Under Pressure

Effect of the Jahn-Teller Distortion on Double Exchange Interaction in La_{0.8}K_{0.2}MnO₃ Nanoparticles

Magnetic Systems at Criticality: Different Signatures of Scaling